Biology Books

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CHAPTER I. BACTERIA AS PLANTS. During the last fifteen years the subject of bacteriology [Footnote: The term microbe is simply a word which has been coined to include all of the microscopic plants commonly included under the terms bacteria and yeasts.] has developed with a marvellous rapidity. At the beginning of the ninth decade of the century bacteria were scarcely heard of outside of scientific... more...

CHAPTER I A REVALUATION OF THE EVIDENCE ON WHICH THE THEORY OF EVOLUTION WAS BASED We use the word evolution in many ways—to include many different kinds of changes. There is hardly any other scientific term that is used so carelessly—to imply so much, to mean so little. Three Kinds of Evolution We speak of the evolution of the stars, of the evolution of the horse, of the evolution of the steam... more...

PREFACE. The general tendency of recent scientific literature dealing with the problem of organic evolution may fairly be characterized as distinctly and prevailingly unfavorable to the Darwinian theory of Natural Selection. In the series of chapters herewith offered for the first time to English readers, Dr. Dennert has brought together testimonies which leave no room for doubt about the decadence of... more...

CHAPTER I THE PROBLEM: THE MODE OF ITS SOLUTION The story of a human life can be told in very few words. A youth of golden dreams and visions; a few years of struggle or of neglected opportunities; then retrospect and the end."We come like water, and like wind we go." But how few of the visions are realized. Faust sums up the whole of life in the twice-repeated word versagen, renounce, and... more...

CHAPTER I. STRUCTURE OF THE BACTERIA AND CONDITIONS GOVERNING THEIR DEVELOPMENT AND DISTRIBUTION. Before one can gain any intelligent conception of the manner in which bacteria affect dairying, it is first necessary to know something of the life history of these organisms in general, how they live, move and react toward their environment. Nature of Bacteria. Toadstools, smuts, rusts and mildews are... more...

In seeking to discover Darwin's relation to his predecessors it is useful to distinguish the various services which he rendered to the theory of organic evolution. (I) As everyone knows, the general idea of the Doctrine of Descent is that the plants and animals of the present day are the lineal descendants of ancestors on the whole somewhat simpler, that these again are descended from yet simpler... more...

by: Asa Gray
These papers are now collected at the request of friends and correspondents, who think that they may be useful; and two new essays are added. Most of the articles were written as occasion called for them within the past sixteen years, and contributed to various periodicals, with little thought of their forming a series, and none of ever bringing them together into a volume, although one of them (the... more...

THE SCIENTIFIC EVIDENCES OF ORGANIC EVOLUTION. Although it is generally recognised that the Origin of Species has produced an effect both on the science and the philosophy of our age which is without a parallel in the history of thought, admirers of Mr. Darwin's genius are frequently surprised at the ignorance of his work which is displayed by many persons who can scarcely be said to belong to the... more...

INTRODUCTORY. The problem of the genesis of species stated.—Nature of its probable solution.—Importance of the question.—Position here defended.—Statement of the Darwinian Theory.—Its applicability to details of geographical distribution; to rudimentary structures; to homology; to mimicry, &c.—Consequent utility of the theory.—Its wide acceptance.—Reasons for this, other than, and... more...

IN the last Lecture I endeavoured to prove to you that, while, as a general rule, organic beings tend to reproduce their kind, there is in them, also, a constantly recurring tendency to vary—to vary to a greater or to a less extent. Such a variety, I pointed out to you, might arise from causes which we do not understand; we therefore called it spontaneous; and it might come into existence as a... more...